Generally in a three-dimensional laminate modeling, cross-sectional shape data is created by slicing three-dimensional shape data of a modeled object that is created by CAD (Computer Aided Design). Then, based on the cross-sectional shape data, thin plates having a cross-sectional shape obtained by slicing the modeled object are created and laminated as in a case where a three-dimensional contour map is created, thus forming the modeled object. The three-dimensional laminate modeling is a modeling method as described above and one method of additive manufacturing.
For example, examples of the three-dimensional laminate modeling include optical modeling that uses a light-curing resin, powder laminate modeling that uses powder, fused-resin deposition modeling that deposits a fused resin, and laminated object manufacturing that laminates paper sheets, plastic sheets, or thin plates of metal or the like, depending on materials used for modeling.
Further, examples of the three-dimensional laminate modeling include, as a system of creating a thin plate, an inkjet system of creating a thin plate of a cross-sectional shape by injecting a minute amount of liquid. In the three-dimensional laminate modeling by the inkjet system, the powder laminate modeling, the fused-resin deposition modeling, the optical modeling, and the like are put into practical use.
For example, in the powder laminate modeling, a layer made of starch or powder of gypsum or ceramics is formed, a binder is injected on a surface thereof by an inkjet, and the powder is firmly fixed by the binder drawn in accordance with a cross-sectional shape, thus forming a thin plate. Further, in the fused-resin deposition modeling, fused wax or the like is injected by an inkjet and the wax or the like drawn in accordance with a cross-sectional shape is solidified, thus forming a thin plate. In the optical modeling, a liquid light-curing resin is injected by an inkjet to form a layer and the layer of the light-curing resin is cured by light applied in accordance with a cross-sectional shape, thus forming a thin plate.
In addition, Patent Document 1 discloses powder laminate modeling using salt powder. For example, Patent Document 1 discloses that “when a liquid containing water as a main component is sprayed, salt powder is dissolved into the sprayed liquid and a volume is decreased, and a fluctuation in layer thickness is caused. If salt is dissolved into an injected liquid up to saturation or a state close thereto, the salt powder is not dissolved when the liquid is injected or sprayed to the salt powder. Thus, as a result of keeping a thickness of the powder layer constant, dimension accuracy can be improved”.
Further, Patent Document 1 discloses, as an effect of the invention thereof, that “a model that is soluble in water, easy to be detached from a mold, and harmless can be realized” and “the combination of salt and an fixing agent with heat resistance imparts heat resistance as well as disappearance property, and a disappearance model model for precision casting can be realized”.
Patent Document 1: Japanese Patent Application Laid-open No. 2004-82206